The present invention relates to generally a multi-nozzle print head for ink jet printers of the type wherein the ink jets issue under the same pressure through all the ink jet nozzles from a common ink chamber.
In general, in the prior art multi-nozzle head, because the ink under pressure flows into the ink chamber through an ink supply inlet formed through one end wall of the head the ink pressure decreases in the ink chambers distant from the ink inlet hole and consequently the ink is jetted under various pressures through the nozzles. As a result, ink drops of the same size are not jetted from the nozzles and consequently the ink drops deposited on a recording medium vary in size from one nozzle to another, resulting in irregularities of recorded patterns.
In order to overcome this defect, there has been invented and used a multi-nozzle head of the type wherein the ink under pressure is made to flow through a plurality of ink distributing pipes spaced apart from each other in the direction of the ink jet nozzles and communicated with an ink pressure equalizing pipe extended to the exterior of the main body of the head, whereby the uniform pressure distribution in the ink chamber may be ensured. However, in practice this arrangement is disadvantageous in that the interconnection between the main body and the pressure equalizing pipe through a relatively large number of ink distributing pipes is cumbersome and therefore the manufacturing process is very time-consuming.